The Mind and its World provides a clear and accessible introduction to a cluster of contemporary controversies in the area of the philosophy of mind and language. Since Descartes, the mind has been thought to be in the head', separable from the world and even from the body it inhabits. Gregory McCulloch, in The Mind and its World , considers the latest debates in philosophy and cognitive science about whether the thinking subject actually requires an environment in order to be able to think. McCulloch explores the argument from Descartes , through Locke, Frege and Wittgenstein up to the present day. He then offers an original defence of his own version of externalism - that the mind is constituted by the objects which are its phenomena.